You could have a bad micro switch, wiring connection, fuse, or relay.
There will only be voltage present at the micro switches when the ignition switch is turned on.
Here are links to the headlight wiring diagrams:
http://www.panteraplace.com/El...AND%20DOORS%20P1.pdf
http://www.panteraplace.com/El...AND%20DOORS%20P2.pdf
John
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